Increasing demand for more powerful and convenient data and information communication has spawned a number of advancements in communications technologies, particularly in wireless communication technologies. A number of technologies have been developed to provide the convenience of wireless communication in a variety of applications.
In many common applications (e.g., laptop computers, mobile phones), it is often desirable or necessary to incorporate two or more different wireless communication technologies in a single device. Especially in consumer products, demand exists for the devices having multiple wireless technologies. Consider, for example, a laptop computer. It may be desirable to incorporate a short-range wireless technology for user interface functions (e.g., wireless voice headset), while at the same time incorporating a different wireless technology for high-speed system data communications (e.g., a wireless LAN). Other examples include mobile phones with Internet access, personal digital assistants (PDAs), and other similar compact data and information communication devices.
Unfortunately, current wireless communication technologies often conflict with each other, presenting system designers with a number of challenges and problems. Most common wireless technologies operate within one of only a few unlicensed high-frequency transmission bands. Thus, many different technologies are designed to operate within a given high-frequency band (e.g., 2.4 GHz). Use of the same high-frequency band is usually not a problem where two applications, utilizing two different wireless communication technologies, are separated by some significant distance. However, in applications where two different wireless communication technologies, attempting to use the same transmission band, are very close together or collocated within a single device (e.g., mobile phone, laptop computer), a number of problems arise. As the different technologies attempt to compete for simultaneous access to the transmission band, contention and loss of data packets can result in significant reductions in the quality and integrity of data transmission.
In the past, several attempts have been made to address this contention problem. Most such attempts have involved either: 1) incorporating only a single wireless communication technology within a given device (i.e., limitation); or 2) requiring an end-user to select only one of multiple available wireless communication technologies to be active at any given time (i.e., end-user arbitration). In the first approach, a particular device was limited to incorporating a single wireless technology. For example, an end-user ordering a laptop computer was given the choice between including either wireless LAN technology or Bluetooth technology, but not both, in their computer. In the second approach, an end-user was provided with multiple wireless technologies, but was required to manually arbitrate between the two because simultaneous operation was not possible. For example, a PDA user would have to manually switch from wireless Internet operation to hot-synch operation, and back again, because the technologies for each function could not operate on the same transmission band simultaneously.
Some prior methods have attempted to address the issue of simultaneous operation by physically separating the antennas through which each technology accesses the transmission band. Because many wireless technologies are relatively short-range, contention problems between technologies can be reduced or eliminated with enough physical separation between antennas. Unfortunately, the number of antennas required by certain technologies (e.g., wireless LAN), and the extremely small size certain end-user equipment (e.g., mobile phones) drastically reduce, if not eliminate completely, the usefulness of such an approach.
As a result, there is a need for a system that provides simultaneous operational coexistence of collocated wireless communication technologies within a single transmission frequency band, providing robust high-performance communication in an easy, efficient and cost-effective manner.